LAKY^ OF WATEE-FLIES. 249 



As Dragon-flies have an " incomplete metamorpliosis," their 

 larvae have more or less a resemblance to themselves, the 

 full-grown insects. The resemblance is in shape, certainly 

 not in colour, which is generally dark brown and very like in 

 shade to the mud upon which the larvae frequently crawl and 

 himt for their prey. They are nearly the most predaceous 

 of all aquatic larvae, and they are more ravenous still, if 

 possible, when they become pupae. Though they are so 

 greedy, they have at the same time a wonderful power of 

 fasting, and wiU live, seemingly in perfect health, without 

 apparently eating anything at all. 



One of the best ways of procuring the larvae of Dragon- 

 flies is to sweep the bottoms of ponds, or rather deep ditches, 

 with the net, or to fish up with a hook, fastened to the end 

 of a cord or stick, the tangles of weeds which have sunk 

 there, and lift them on the bank. After watching such 

 dripping masses for a minute or two, most likely several larvae, 

 together with other insects of different species, will be seen 

 crawling about the mud and the decaying plants which have 

 been thus drawn out of the pond or ditch. Some of the larvae 

 will be exactly of the colour of the mud ; others will be nearly 

 black; while a few, perhaps, will be covered, more or less, with 

 confervas. They will be, if there are many of them, most 

 likely of different shapes, sizes, and ages. In fact, some of 

 thefii ought to be called pupae rather than larvae, for the 

 signs of wings in their cases will show that they have arrived 

 at their nymph stage. 



On examining many larvae of Dragon-flies taken from two 

 or more pieces of water, one will conclude that they may be 

 divided, on account of their various forms, into at least three 

 groups. The first animal to be noticed, perhaps, owing to its 

 strong and bold appearance, will be in shape like a, Fig. 155. 

 This will be the larva of one of the Mschnidas. Then there 

 will be another insect, having much the appearance' of the 

 preceding, but stouter and clumsier. The eyes are smaller 

 and fiurther apart, and the head is more square; sometimes 

 it will be more or less covered with foreign matter (6, Fig. 1S6). 

 This larva is a representative of the Lihellulides. And, lastly. 



